1. Field of the Invention
The present invention relates to a method for controlling semiconductor fabricating equipment and, more particularly, to a method for preventing operational problems due to continuous operation of semiconductor fabricating equipment without any maintenance by automatically interlocking the equipment.
2. Description of the Related Art
As technology improves in the electronics industry, there has been a trend toward high integration, i.e., providing more functions in far smaller electronic devices using high density semiconductor devices. Such semiconductor devices are fabricated through highly precise processes performed in sequence by sophisticated and complex semiconductor fabricating equipment, e.g., thin film deposition equipment and etching equipment, arranged on a semiconductor fabrication processing line.
Such semiconductor fabricating equipment are on-line connected to a host computer which provides the controlling functions. An operator inputs an operation commencing command through an operator interface personal computer (O/I PC) that is on-line connected to the host computer. When the operation commencing command is input into the host computer, the host computer retrieves process data stored therein and downloads the retrieved process data into a corresponding semiconductor fabricating equipment. Thereafter, a lot of workpieces to be processed, e.g. a cassette of 25 wafers, is loaded into the corresponding semiconductor fabricating equipment by the operator or a transferring apparatus. The corresponding semiconductor fabricating equipment then performs a predetermined process with the lot according to the downloaded process data.
While the wafers in the lot are processed in the corresponding semiconductor fabricating equipment, the operator monitors the operating state of the equipment and the processed state of the wafers and records the monitoring results as data in a predetermined format on a storage device provided with the equipment. The recorded information generally includes the number of wafers actually processed by the equipment. When the operator changes, the operating state of the equipment and the processed state of the wafers are continuously recorded by another operator.
The recorded data are used for maintenance of the semiconductor fabricating equipment. Maintenance includes, for example, cleaning units such as a chamber of the semiconductor fabricating equipment, or replacing the units with new ones. The operator compares the number of wafers actually processed by the equipment to a reference number of wafers associated with the equipment, for example, the number of wafers that may be processed between maintenance cycles. According to the compared result, the operator may stop the operation of the semiconductor fabricating equipment and carry out appropriate maintenance.
However, such a conventional method suffers from a disadvantage that the comparison to determine whether maintenance is required cannot be carried out rapidly or without error. It takes a large amount of time for the operator to compare the recorded data with the reference data and determine whether to carry out the maintenance or not. In addition, in the event that the operator inadvertently fails to notice when to carry out the maintenance, the equipment would be continuously operated under poor conditions, which causes operational problems later.